Rotary expansible descaler for boiler tubes and the like



March 14, 1950 v H BAKER ET AL 2,500,238

ROTARY EXI ANSIBLE DESCALER FOR BOILER TUBES AND THE LIKE Filed July 29,1947 2 Sheets-Sheet l VIRGIL H. BAKER, &' Cap; (7. flzvaaasom March 1950v. H. BAKER ETAL 2,500,238 ROTARY EXPANSIBLE DESCALER FOR I BOILER TUBESAND THE LIKE Filed July 29, 1947 2 Sheets-Sheet 2 W v M Patented Mar.14, 1950 UNITED STATES OFFICE B0 TARY EXPANSIBLE DESCALER 'FQB BOILERTUBES AND {THE LIKE Virgil H- Bake an C M- A de son Strin field, Ohio,assignors to Elliott pompany, J cannette, Pa", a corporation ofRennsylyan'ia Application July-29, 1947, Serial No. 764,456

6 Claims. ((51. 1,5,??10413.)

This invention relates to expanding tools or heads for cleaning tubes,and more particularly to power driven heads especially suitable forcleaning security circulators and thermic siphons in railroadlocomotives.

It is among the objects of this invention to provide such an expandingcleaner head which is short and compact, which has a simple and ruggedconstruction, which is relatively inexpensiveto make, and which canexpand from a small diameter to .a comparatively large size.

In accordance with this invention, each of a plurality of parallelspacing members is in the form of a channel which is substantially V-shape in cross section. These members are rigidly connected insuch amanner as to be supported in a circle with their apex edges pointedtoward its axis and their sides spaced apart to form slots between themhaving parallel side walls. These walls are provided with transverseholes through their rear ends. An arm normally lies in each of the slotsand has a passage through its rear end in which there is a pivot pinthat projects into the adjacent wall holes. The pins are held in placemost suitably by prongs projecting forward into the channels from aretaining member at their rear ends. The rear end of the head is adaptedto be connected to driving means for rotating the head to swing the armsout of the slots. A spider is slidably disposed in the slots and ispivotally connected by links to the front end portions of the-arms inorder to link the arms together so that all must swing together and thesame distance. Cutting members, such as toothed wheels or rollers, arerotatably mounted on the front ends of the arms. The links preferablyare connected to the spider by pivot pins which are held in place by theside walls of the slots. When the arms are collapsed, the links extendforward along the arms and have their front ends connected to the armsby pivot pins which preferably have reduced end portions that projectinto holes in the links. With this construction the links, which areprevented by the side walls of the slots from spreading apart, preventthe pivot pins at their front ends from slipping out of the arms. Thedistance that the arms can swing outward can be limited by their rearends striking an obstructiomsuch as a connecting member that unites thechannels.

The preferred embodiment of the invention is illustrated in theaccompanying drawings in which Fig. 1 is a view of the cleaning headcollapsed; Figs. 2 and 3 are transverse sections taken on the lines IIII and III-I II, respec- 2 r y. p R Fi 4 i a s new .of t fully expandedhead, but with the lower half shown in section, and Fig. 5 ,afragmentary cross section of an arm taken on the line V V of Fig. f1.

R rin o th d w s. 0 m ta hannels l, each of which-forms a right angle incross section, are arranged in a circle with their inner or apex edgespointing ,toward the .axi yOf the circle. The channels are spaced equaldistances apart to f m b tw e t e sl s wh c .he parallel side wallsformed by the sides of the channels. The channels are held rigidly inthis position .by means, of a connecting member which, preferably, is.asolid metal block 3 integral-with the rear end apex portions of thechannel as shown in Figs. 3 and 4. Integral with the ghlQGk is athreaded stud 4 which projects rearward for a purpose to be describedpresently.

Lying in each slot ;2, when the head is collapsed, ;is an arm 6 thatprojects from the front end of theslot. There is .a passage through therearendof each arm and apivot pin .1 extends through the passage and hasits ends projecting into holes through the rear ends of the adjoininghannel walls. To keep the pins from slipping out of ,place, a retaininmember is employed which has a disc-like body ,8 engaging the rearendsof the channels ;I and ,block '3 and having a central p i h ugh whict re ded stud ex ends. Thi bo y i provid d with inwardly extendingprongs .9 whichslide into the ,rear end portions of the channels andoverlie the ends of pivot pins 1 to lock them in place. The re,- tainingmember is held in place by a coupling sleeve H screwed onto stud 4. Therearend of h nce-s in is ada te to be connec ed to th drive shaft of amotor (not shown) which rapidly rotates the head and thereby,throughcentrifugal force, causes the front ends of the arms to swingoutward.

in order that the head will clean the tubular member ,in which it isdisposed, the vfront ,end of each .arm 6 ,is provided with .a rearwardly.extending ,:bore ylIl which a headed ,pin 12 is inserted. 'Rotatable onthe projecting portion of the pin is ,a toothed .cutting :wheel 13 :ofconventional form. When the arms are :collapsed in slots '2, the headedspins converge forward :as shown in Fig. 1, so that the cutting wheelsvill not project radially beyond the periphery of the rest of the head.

When this cleaning head is used ina thermic siphon which is providedwith a longitudinal slot through its wall, ,it is necessary to keep arms16 from ,iflying out through :the slot as the need .130?

tates. This is accomplished by linking all of the arms together so thatthey all must swing out and in in unison; the greatest distance that anyarm can swing away from the axis of the head thereby being limited bythe maximum distance that any other arm can swing away from the axis. Inaccordance with this invention, the tying together of the arms is donepartly by means of a cross-shape block or spider it slidably disposedbetween channels I. The parts of the spider that project into slots 2are considerably narrower than the slots to permit the rear ends ofpairs of links H to be interposed between the sides of the spider andthe channels. The spider has passages therethrough in which are disposedpivot pins 18 that project into holes in the adjoining links. These pinsare held in place by the channel walls at their ends as shown in Fig. 2.The pins l8, spider, and links are assembled and then slipped into thefront ends of the slots before the rear ends of arms 6 are at tached tothe channels.

The inner surfaces of the arms are provided with recesses at thataccommodate the spider when it is in its rearward position, indicated bybroken lines in Fig. 4, adjacent the connecting block 3. The sides ofthe arms are provided with recesses 21 along which links H extend whenthe arms are collapsed in the slots. The front ends of the links areconnected to the arms in front of the channels by means of pivot pins22. Each pin extends through a passage in an arm and, as shown in Fig.5, has projecting end portions of reduced diameter that extend throughholes in the adjoining ends of the links. As each pair of links isprevented by the side walls of a slot 2 from spreading apart, the frontends of the links keep their pivot pin 22 from slipping out of theadjoining arm. 'Of course, the links are slipped over the ends of thispin before the spinder is inserted in the slots. Pin 22 also extendsthrough a notch in the side of the adjoining headed pin [2 to lock thelatter in the arm.

To prevent the front ends of arms 6 from swinging so far out of theslots that the adjoining links pull the spider either out of the slots,or into a position in which it will be aligned with the links so thatthe assembly will act like a straightened toggle that would prevent thearms from collapsing, the expansion of the arms is limited. This isaccomplished by providing the rear ends of the arms behind pins 7 withsurfaces 23 that swing inward as the front ends of the arms swingoutward. These surfaces will strike the connecting block 3 and stop theoutward movement of the arms before the spider can be pulled forwardinto a locking position. 1

It will be seen that this cleaning head is relatively short and compactbecause nothing extends ahead of the headed pins on which the cuttingwheels are mounted. The spider is surrounded by the arms and channels ina well protected position. It will be noticed in particular that none ofthe parts of this head are riveted together, and that the only threadedmember is the stud that receives the coupling by which the head isconnected to the driving motor. Consequently, the cost of assembling thehead is reduced. The head also can be quickly disassembled for repair bymerely unscrewing the coupling so that the retaining member can beremoved. The various pivot pins then can be pushed out of posi tion sothat the different element will come apart. By not having to use rivets,pivot pins of larger diameter can be employed, thereby increasing thestrength of the connections. The cleaner head disclosed herein can bemade of such a size that when collapsed, it can pass through an openingof 2% inches diameter, and then expand sufficiently to clean the insideof a tube of '2 inch diameter. This is necessary for cleaning thermicsiphons.

According to the provisions of the patent statutes, we have explainedthe principle and construction of our invention and have illustrated anddescribed what we now consider to represent its best embodiment.However, we desire to have it understood that, within the scope of theappended claims, the invention may be practiced otherwise than asspecifically illustrated and described.

We claim:

1. All expanding head for cleaning tubes and the like, comprising aplurality of parallel spacing members, each member being in the form ofa channel substantially V-shape in crosssection, means rigidlyconnecting said members to support them in a circle with their apexedges pointing toward the axis of the circle and their sides spacedapart to form slots between them having parallel side walls providedwith transverse holes through their rear ends, and arm normally lying ineach of said slots and having a passage through its rear end, a pivotpin disposed in said passage and projecting into the adjacent wallholes, the rear end of the head being adapted to be connected to drivingmeans forrotating the head to swing the arms out of the slots, a spiderslidably disposed in said slots, the opposite sides of each arm beingprovided with recesses, links normally lying in said recesses with theirfront ends pivotally connected to the arms and their rear ends pivotallyconnected to the spider to link the arms together so that all of themmust swing in unison, and cutting members rotatably mounted on the frontends of the arms.

2. An expanding head for cleaning tubes and the like, comprising aplurality of parallel spacing members, each member being in the form ofa channel substantially V-shape in cross section, means rigidlyconnecting said members to support them in a circle with their apexedges pointing toward the axis of the circle and their sides spacedapart to form slots between them having parallel side walls providedwith transverse holes through their rear ends, an arm normally lying ineach of said slots and having a passage through its rear end, a pivotpin disposed in said passage and projecting into the adjacent wallholes, the rear J- end of the head being adapted to be connected todriving means for rotating the head to swing the arms out of the slots,a spider slidably disposed in said slots, links pivotally connected tothe front end portions of the arms and extending rearward to the spider,pivot pins connecting the links to the spider and being substantially aslong as the width of said slots so that said last-mentioned pivot pinsare held in place by said side walls, and cutting members mounted on thefront ends of the arms.

3, An expanding head for cleaning tubes and the like, comprisingaplurality of parallel spacing members, each member being in the form ofa channel substantially V-shape in cross section, means rigidlyconnecting said members to support them in a circle with their apexedges pointing toward the axis of the circle and their sides spacedapart to form slots between them having parallel side walls providedwith transverse holes through their rear ends, an-arm normally lying ineach of said slots and having a passage through its rear end, a pivotpin disposed in said passage and projecting into the adjacent wallholes, the rear end of the head being adapted to be connected to drivingmeans for rotating the head to swing the arms out of the slots, a spiderslidably disposed in said slots, pairs of parallel links engaging thespider and spacing it from said side walls, a pivot pin connecting therear end of each pair of links to the spider and being substantially aslong as the width of the slot in which it is disposed so that the pin isheld in place by said side walls, means pivotally connecting the frontend of each pair of links to an arm, and cutting members mounted on thefront ends of the arms.

4. An expanding head for cleaning tubes and the like, comprising aplurality of parallel spacing members, each member being in the form ofa channel substantially V-shape in cross section, means rigidlyconnecting said members to support them in a circle with their apexedges pointing toward the axis of the circle and their sides spacedapart to form slots between them having parallel side walls providedwith transverse holes through their rear ends, an arm normally lying ineach of said slots and having a passage through its rear end, a pivotpin disposed in said passage and projecting into the adjacent wallholes, the rear end of the head being adapted to be connected to drivingmeans for rotating the head to swing the arms out of the slots, a spiderslidably disposed in said slots, pairs of parallel links engaging thespider and spacing it from said side walls, a pivot pin connecting therear end of each pair of links to the spider and being substantially aslong as the width of the slot in which it is disposed so that the pin isheld in place by said side walls, the front ends of the links beingprovided with holes therethrough, a pivot pin loosely mounted in eacharm and having ends of reduced diameter projecting into said holes inthe adjoining pair of links, the width of said slots being such thattheir side walls substantially engage the links to keep each pair ofparallel links from moving away from the arm between them, and cuttingmembers rotatably mounted on the front ends of the arms.

5. An expanding head for cleaning tubes and the like, comprising aplurality of parallel spacing members, each member being in the form ofa channel substantially V-shape in cross section, means rigidlyconnecting said members at their rear ends to support them in a circlewith their apex edges pointing toward the axis of the circle and theirsides spaced apart to form slots between them having parallel side wallsprovided with transverse holes through their rear ends, an arm normallylying in each of said slots and having a passage through its rear end, apivot pin disposed in said passage and projecting into the adjacent wallholes, means at the rear ends of said channels adapted to connect thehead to driving means for rotating it to swing the arms out of theslots, a spider slidably disposed in said slots in front of saidfirst-mentioned connecting means, links pivotally connecting the spiderto the front end portions of the arms to link the arms together so thatall must swing in unison, and cutting members mounted on the front endsof the arms.

6. An expanding head for cleaning tubes and the like, comprising aplurality of parallel spacing members, each member being in the form ofa channel substantially V-shape in cross section, means rigidlyconnecting the rear ends of said members to support them in a circlewith their apex edges pointing toward the axis of the circle and theirsides spaced apart to form slots between them having parallel side wallsprovided with transverse holes through their rear ends, an arm normallylying in each of said slots and having a passage through its rear end, apivot pin disposed in said passage and projecting into the adjacent wallholes, the rear end of the head being adapted to be connected to drivingmeans for rotating the head to swing the arms out of the slots, a spiderslidably disposed in said slots in front of said first-mentionedconnecting means, links pivotally connected to the spider and extendingforward along the sides of the arms in the slots, means pivotallyconnecting the front ends of the links to the arms so that all arms mustswing in unison, and cutting members rotatably mounted on the front endsof the arms.

VIRGIL H. BAKER. CARL M. ANDERSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 901,940 Andrews Oct. 27, 19081,032,193 Elliott July 9, 1915 1,163,661 Haue-r Dec. 14, 1915 1,363,232Darlington Dec. 28, 1920 2,397,156 Reynolds Mar. 26, 1946 FOREIGNPATENTS Number Country Date 479,180 England Feb. 1, 1938 v Certificateof Correction Patent N 0. 2,500,238 March 14, 1950 VIRGIL H. BAKER ETAL.

It is hereby certified that errors appear in the printed specificationof the above numbered patent requiring correction as follows:

Column 3, line 41, for spinder read spider; column 4, line 18, for theword "AIP read An; line 27, for and arm read an arm;

and that the said Letters Patent should be read with these correctionstherein that the 'Z same may conform to the record of the case in thePatent Ofiice.

Signed and sealed this 13th day of June, A. D. 1950.

[SEAL] THOMAS F. MURPHY,

Assistant Gammz'ssz'oner of Patents.

